1. Technical Field
The present invention relates to an image reading device.
2. Related Art
An underside (the surface which faces an original platen glass) of a cover which opens and closes on the original platen glass of a so-called flatbed scanner, which is an example of the image reading device and performs reading of an image of an original which is placed on original platen glass while causing a reading sensor to move, is provided with an original retaining portion which retains the original when the cover is closed. For example, the original retaining portion is configured to include an elastic member formed of sponge, urethane, or the like, and is capable of deforming to an extent according to the shape of the original.
When the original retaining portion is fixed to the underside of the cover, depending on the working accuracy and the assembly accuracy, there is a case in which the pressing force from the original retaining portion does not apply uniformly to the original platen glass surface. Therefore, there is a flatbed scanner in which the influence of the working accuracy and the assembly accuracy of the cover is reduced. This is achieved by providing the flatbed scanner with a configuration which fixes the original retaining portion, which is formed of a laminated structure obtained by interposing an elastic member between a sheet-shaped member which serves as the pressing surface of the original and a reinforcing plate, to the cover using an elastic buffer member.
In such a flatbed scanner, there is a case in which the original retaining portion adheres to the original platen glass when the cover is closed in a state in which no original is placed on the original platen glass. When a user attempts to rotate and open the cover in the state in which the original retaining portion is adhered to the original platen glass, the buffer member or the like peels off of the original retaining portion.
Therefore, for example, in the image reading device of JP-A-2000-261601, a configuration is disclosed in which a sheet-shaped member which is larger than the original platen glass is provided on the original retaining portion by positioning the end portion of the sheet-shaped member at an edge portion which is formed a level higher than the surface of the original platen glass when the cover is in the closed state, a gap is provided between the end portion of the sheet-shaped member and the original platen glass.
However, in the configuration of JP-A-2000-261601, there is a problem in that there is a concern that the adherence of the original to the original platen glass by the original retaining portion will be reduced. The invention solves the problem which comes with the adherence of the original retaining portion to the original platen glass when the cover is rotated while securing the adherence of the original to the original platenlass by the original retaining portion when the cover of the flatbed scanner is closed.